function greet(){
    console.log(" hello ")

}
const speak = function(name = "xyu", time = "night") {
    console.log(`good ${time} ${name}`)
    }
//     speak() 
//     speak("li", "day") 
//     const hello = () => {
//         console.log("hello")
//         }

//     greet()
//     hello()
let email = "mather@google.com"
let result = email.replace("google", "baidu")
console.log(result);